In the fabrication of electronic devices, the interface of devices with other devices becomes more challenging as the device structure increases in speed and complexity. One structure that is utilized to provide an in-package high density interconnect of dies is the Embedded Multi-Die Interconnect Bridge (EMIB) of Intel Corporation.
An embedded interconnect bridge is fabricated in a package, with the technology allowing for construction of high density interconnects between heterogeneous dies on a small package. Instead of requiring an expensive silicon interposer with TSV (through silicon via), a small silicon bridge chip may be embedded in a package, enabling very high density die-to-die connections only where needed. Standard flip-chip assembly may then be used to provide robust power delivery and to connect high-speed signals directly from chip to the package substrate.
However, the fabrication of such an interconnect bridge chip requires the generation of cavities for the embedding of dies within the structure. The formation of such cavities generally requires laser drilling in the package substrate, which is a time consuming and expensive process and thus adds significantly to overall cost and complexity of the fabrication process.